The invention pertains generally to a subscriber terminal for CATV or other subscription television systems and is more particularly directed to a method and an apparatus for reprogramming a subscriber terminal.
The subscriber terminal, more commonly known as a set top terminal, is an integral component of subscription television systems. These subscription television systems can be cable television (CATV) systems, SMATV systems, multi-point, multi-distribution (MMDS) systems, or direct-to-home (DTH) systems. The terminals have conventionally provided the functions of tuning particular channels of the subscription television system which are outside the subscriber's television receiver capability. Further, they provide conditional access to the particular subscription service through authorization codes and in many services provide tiering or authorization of particular channels of the service by descrambling.
More recently, the subscriber terminal has become user friendly by providing an interactive, on-screen display and other user functions that allow the subscriber to manipulate the subscription service and his television receiver in additional ways. These features include such things as volume control, pay-per-view event confirmation, favorite channel listings, sleep timer features, parental control capability, messaging, program timers for recording VCR programs, and other consumer friendly operational features.
In addition, some of the features found in newer television receivers can be provided for older receivers by the subscription terminal. For example, channel identifiers, mute and volume control can be accomplished by the subscriber terminal making the subscriber's television receiver appear to be a newer model with these capabilities.
An advantageous example of a subscriber terminal with these advanced consumer features is the 8600 model series of subscriber terminals manufactured by Scientific-Atlanta, Inc. of Lawrenceville, Ga.
Currently, these subscriber terminals are controlled by programmable microcontrollers which have their control programs stored in a read only memory (either integral with the microprocessor or included in a separate integrated circuit) or stored in a separate non-volatile memory such as an EPROM or a battery backed up RAM. With the current programming methods, the control program of the subscriber terminal can only be changed by removing the memory device (or the device incorporating the memory) and replacing it. This method is very inconvenient and expensive for changes which are to be made to subscriber terminals as it means a home visit from the service personnel of the subscription service provider. Subscription television systems may have several hundred thousand subscriber terminals which may need such upgrades.
Therefore, it would be advantageous to be able to reprogram the subscriber terminals of a subscription television service to change on screen parameters, change subscriber interfaces, add new features, and modify the control program from a remote location.